Let me stick some spaces in some helpful places:
2017 09 19 . 19 00
20170919 means 19th Sep 2017, and
1900 is in 24-hour clock format, IE 7:00PM
Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how they work.
Events on this stardate
This is our Welcome Back Event, aimed mostly at at returning members. That said everyone is welcome if you want to try our society (so bring your friends) we have simply decided to postpone any free pizza until next week to give Freshers a little more notice.
Everyone (9 people going)